Fuse mounting



A. CORBETT FUSE MOUNT ING Sept. 5, 1939.

Filed April 7, 1937 2 Sheets-Sheet l INVENTOR ATTORNEYS A. CORBETT Sept '3 i9 9 FUSE MOUNTING Filed April 7, 2 Sheets-Sheet 2 INVENTOR i -Z Patented Sept. 5, 1939 2, l 1

UNITED STATES PATENT OFFICE FUSE MOUNTING Alfred Corbett, Irwin, Pa., assignor to National Electric Products Corporation, a corporation of Delaware Application April 7, 1937, Serial No. 135,501 4 Claims. (Cl. 200-133) This invention relates to an electrical fuse and in the cooperative mounting of the fuse sockmounting. et and its exterior contact and contact attach- More particularly my invention relates to the ments on the fuse-carrying deck 4. The features combination of a plug fuse socket arranged for comprised in my improvement may be applied to 5 the exposure of a central feed contact at the any fuse socket of usual construction for the re- 5 base thereof with a deck arranged for connection ception of a fuse of the screw plug type compristherebeneath with a current source. ing a downwardly projected center contact and In a more general sense my invention relates arranged to complete a circuit through said to a plug fuse socket having integral therewith center contact to an outwardly disposed contact,

0 means arranged for connection to a line circuit, which latter is in usual practice the circuit conand by means of which the socket may be positact. The improvements, however, have particu tively connected with an underlying insulating lar utility in cooperation with a special arrangestructure of any form independently of the cenment providing for selectivity in the fuses which tral contact element of the fuse socket. may be used with a particular socket, and which 1 As shown, the fuse socket of my invention comarrangement precludes the use of a center con- 5 prises a selective contact screen through which tact screw, or rivet, for attaching the fuse socket an appropriately dimensioned central contact to an underlying insulating body. may be projected to make electrical contact with In its fundamental features this illustrated fuse an underlying live contact element. socket comprises an exterior metallic shell 6, an In the accompanying drawings Fig. I is a front interior insulating cylinder 1, and a bottom struc- 20 elcvationof a fuse box partially broken away to ture comprising a plate 8 of insulating material show in front elevation the fuse mounting in perforate centrally at so, and an interior threaded position therein. shell 9. Desirably, the base of the socket com- Fig. II is a cross-sectional View, taken on the prises a m t l c pl e ill h v a ntr l p n n plane of section line II-II of Fig. I, showing the Illa in line with the opening 3a through the insufuse mounting of my invention'in position thereat ng plate but of a lesser diameter. and a cenin. trally perforate light-weight insulating disc 24 Fig III is a exploded vie taken partly in overlying the metallic disc. With this arrangeelevation and partly in vertical section, showing m nt cen ral fe Contact depends p n the p the fuse-carrying deck, the plug fuse socket, and jection of a central contact carried by the fuse a cover plate in position for installation of the through the central opening in the base of the fuse socket on the deck. socket. This may be effected only by a fuse, such Fig. IV is a vertical sectional detail view of the as the fuse H shown, which has a center conplug fuse socket of my invention, showing the cirtact l2 of such restricted diameter that it may cuit contact integrated therewith, and binding p oj ct through e pe g m which is the 35 screws in position for mounting the socket to most restricted of the central openings. to make the fuse-carrying deck. electrical contact with a live contact, such as the Fig. V is a bottom plan view of the fuse socket ntact scr w l7 sh wn in h win and the circuit contact member integrated there- With this structure. the mounting means prilO with.

marily comprise a contact element M of conduc- Fig. VI is a fragmentary, vertical, sectional view tive metal, which is projected radially from the of the fuse-carrying deck, showing the fuse sockfuse socket adjacent the base of the socket. This et partially in elevation and partially in vertical Contact element is secured to the cylindrical body section mounted thereon. of the fuse socket for p r In the drawings reference numeral l designates therewith, and in electrical contact with the ex-- a fuse box in which are installed a plurality of terior metallic shell of the socket. This permanfuse-carrying decks. These decks 4, as shown in ent integration may be by welding or soldering Fig. II of the drawings, are mounted in assembly the contact to the shell, but I may alternatively with buss bars 3; and, as is shown in Figs. I and utilize the mode of permanent attachment which 0 II, carry cover plates 2 which are spaced bodily is shown in the drawings.

from the face of the decks to surround the upper As shown, the region of the contact element l4 edges of upwardly open sockets 5 for the reception which lies beneath the fuse socket is formed as a of plug fuses. torus I 5 which lies against the non-conductive Figs. II, III, and VI of the drawings show the base plate 8 in a position in which it does not ob- 5 mounting of a circuit contact to a fuse socket, struct the central opening 8a in the base plate.

As shown, throughout a portion of its circumference the torus l5 of the contact member 14 is clamped to the insulating base plate 8 by a flange or lip 16, which is inturned at the lower edge of the exterior metallic shell 5, and is forced firmly against the under surface of torus I5, firmly and permanently to engage the radial contact element [4 to the body of the fuse socket.

This arrangement is useful for the attachment of any fuse socket for receiving a fuse of the screw plug type to an underlying insulating body. It is of particular utility in attaching a fuse socket of the specialized tamper-proof and se lective type herein shown to an underlying insulating body, and is of particular utility in mounting a socket of that type on a fuse-carrying deck, such as the fuse-carrying deck shown, Which has a live or feed contact extended therethrough to provide for the making of feed contact to the fuse at the upper surface of the deck.

In this specific assembly the deck 4 has extended therethrough a screw ll, which is adapted to carry an element for making electrical contact with a buss bar 3 beneath the deck, or is arranged of itself to make electrical contact with such buss bar. The head l'la of the contact screw lies upon, and projects slightly above, the upper surface of the deck 4. In establishing an electrical circuit through the fuse, the center contact [2 of the fuse is caused to project through the central opening 811 in insulating base plate 8 a distance suflicient to bring the center contact of the fuse firmly to bear against the'head Ila, of the contact screw H.

In mounted position of the fuse socket on the fuse-carrying deck, as shown in Fig. VI, the radially extended contact i l, which as usual is here the circuit contact of the fuse, raises the body of the fuse socket sufficiently from the upper surface of the deck 4 that the head 1m of contact screw l! is received in the space defined by the torus I5 which forms the inward portion of the contact member. In the radially extended body of contact member I4 there is a pair of openings 18 and IQ, for securing the contact member and fuse socket assembly to the deck, and for making circuit connection to the contact member. A screw 20, passed through opening l8 and having threaded engagement in a thimble 2| inset in the body of the deck, serves to secure the contact member and the socket assembly to the deck. Dependent around opening 19 is a fillet iSa, which enters a cavity 22 in the deck. A binding screw 23 has a threaded engagement in the thickness of the contact body surrounding opening [9 and in the fillet Na, and projects into the cavity 22 in the deck.

It will be seen that the fuse socket assembly is secured to the fuse-carrying deck by means of the radially extended circuit contact, and is not secured by means of the centrally disposed feed contact. Also, the socket assembly receives within its general structure, but outside the tamper-proof interiorly disposed elements of the socket, the central feed contact which is extended through the deck structure.

It will readily be seen that the fuse socket mounting is adapted operatively to secure a fuse socket to underlying insulating structures other than the deck shown; and that for such general purpose it is particularly accommodated to the use of cooperative tamper-proof and selective features in the fuse and fuse socket. It is, however, of general utility, since the use of the radially extended circuit contact integral with the fuse sockets, for mounting the fuse socket on an underlying insulating structure, makes for convenience in making mounted assembly of the fuse socket in a panel board, or like structure, which comprises a great number of fuse sockets.

I claim as my invention:

1. As an integral element, a socket for plug fuses comprising a cylindrical shell of electrically conductive metal, a non-conductive base mounted in said shell, a peripherally extended contact bar having a portion lying beneath said non-conductive base and within the periphery of the shell, and a flange projected radially inward from the lower edge of the shell and engaging the contact bar between it and the non-conductive base in permanent integration in the socket structure and in electrical contact with the shell.

2. A fuse mounting assembly comprising the combination of a fuse-carrying insulating deck having extended therethrough a contact member adapted to make electrical contact with a live electrical conductor beneath the deck and to make electrical feed contact with a fuse above the deck; with a fuse socket comprising a metallic outer shell, a base providing in said. metallic shell and arranged to permit selective projection of a fuse contact therethrough to meet the deckcarried contact, and a peripherally extended contact member integrated in the fuse socket structure and in permanent electrical contact with the outer metallic shell of the fuse socket.

3. As an integral element, a socket for plug fuses comprising a cylindrical shell of electrically conductive metal, a non-conductive base mounted in said shell, a peripherally extended contact bar having a portion'lying beneath said nonconductive base and within the periphery of the shell, in permanent integration with the shell, and an opening for the center contact of a plug fuse in said non-conductive base and removed both from said conductive shell and the peripherally extended contact bar permanently integrated therewith.

4. As an integral element, a socket for plug fuses comprising a shell of electrically conductive metal, a contact bar having a portion lying within the periphery of the shell at the lower end thereof in permanent integration with the shell and a portion extended peripherally beyond the shell, and an opening in the portion of the contact bar lying within the periphery of the shell for projection of the center contact of a plug fuse downwardly from the shell and out of contact with the said contact bar.

ALFRED CORBETT. 

